Air valve



p 1967 A. SCHONFELD ETAL 33 AIR VALVE Filed Aug. 30. 1965 INVENTORS ARNOLD SCHONFELD MARViN JACOBY United States Patent 3,342,450 AIR VALVE Arnold Schonfeld, Levittown, and Marvin Jacoby, Fort Washington, Pa., assignors to Sperry Rand Corporation, New York, N.Y., a corporation of Delaware Filed Aug. 30, 1965, Ser. No. 483,744 9 Claims. (Cl. 251--75) This invention relates to air valves, but more specifically to such valves which are particularly useful in keyboards of fluid actuated devices, such as pneumatic typewriters, calculators or the like.

The primary object of the invention is to provide an improved push button or key actuated fluid valve whereby fluid flow may be switched on and off.

In accordance with the above and first briefly described in connection with its preferred form the invention comprises at least a pair of channels arranged for fluid flow from one to another and key operated spring valve means for switching the flow on and off between the channels.

In the drawings:

FIGURE 1 is a front elevational view, partly in section, of a fluid valve in accordance with the preferred form of the invention;

FIGURE 2 is a view taken along line 22 of FIGURE 1, with the valve in its OFF condition;

FIGURE 3 is a view similar to FIGURE 2 but showing the valve in its ON" condition; and

FIGURE 4 is a perspective view of the spring valve element for controlling the fluid flow.

As seen in FIGURE 1, a pair of channels and 12 are provided in a key base 14 and terminate at a planar top surface 16 of an enlarged head portion 18 of the base. A push button or key 20 is fitted over and in spaced relation with the top surface and captured thereon by turning or snapping in its lower edges under the enlarged head, as seen at 22.

Fitted in the space between the key and surface 16 is a leaf spring valve element 24 which, in addition to controlling the fluid flow between channels 10 and 12, also urges the key to its normal retracted position. As seen in FIGURE 4, the spring valve element 24 comprises a fiat rectangular portion 26 and upwardly and outwardly turned weak tines or fingers 30 at each corner.

In this form of the invention, it is the tines 30 which urge the key to its retracted inoperative condition, as seen in FIGURES 1 and 2. In addition, and because they are weaker in strength than the portion 26, they provide a degree of pre-travel of the key 20 before the flat portion bows to permit air to flow between the channels 10 and 12, as described more fully below.

In operation, fluid, such as air, is introduced into one or the other of channels 10 and 12, let us say 10, but is normally prevented from entering channel 12 by the spring valve element 24 which as seen in FIGURE 1, is pressed against surface 16 by the tines 30, thus to block both channels at surface 16. When the key 20 is depressed, as shown in FIGURE 3, its first movement bends the weak tines 30 for a certain amount of pre-travel to give the operator the proper feel of the usual key operation, after which the shoulders 32 on the inner side of the end walls 33 of the key contact the opposite edges 34 of the flat portion 26 of the spring 24. Continued downward movement of the key bows the spring, as seen in FIGURE 3, opening the inlet and outlet ports 36 and 38, respectively of channels 12 and 10, so that the air can flow from channel 10 into channel 12. Release of key 20 permits the spring to resume its normal condition again shutting off the ports 36 and 38 and at the same time returning the key to its retracted inoperative condition, as seen in FIGURE 2.

To increase the proper feel of key depression, the flat portion 26 of the spring 24 may be formed to snap or click when depressed, such as with the well known cricket simulating toys. The escape of air from around the key when depressed is prevented by reason of the close arrangement of the key side walls 40 with the sides of the head 18, and the contact of shoulders 32- with spring ends 34. Alternatively, the escape of air may be prevented by bottoming the key on fixed structure, as indicated at 42 in FIGURE 3.

If desired the valve construction may be simplified by omitting the tines 30 and lengthening the key shoulders 32 to rest directly upon the spring ends 34. Also instead of having two channels, as shown, one may be provided through the key to dump the air to atmosphere upon actuation of the key.

The embodiments of the invention in which an eX clusive property or privilege is claimed are defined as follows:

1. A fluid flow control valve comprising:

(A) a base structure having (1) a top surface,

(2) a fluid input channel having an input port in said surface, and

(3) a fluid outlet channel having an outlet port in said surface (B) a spring leaf valve element positioned on said surface over said ports in a manner preventing fluid flow therebetween;

(C) a key positioned over said valve for relative movement therewith; and

(D) means responsive to movement of said key in a direction toward said valve to cause the valve to assume a bowed shape over said input and outlet ports thereby opening said ports for fluid flow from the one to the other respectively.

2. A valve according to claim 1 wherein:

(A) said top surface (1A1) is substantially flat, and

(B) said spring leaf element (1B) is substantially flat.

3. A valve according to claim 1 wherein:

(A) said base structure (1A) has a head portion topped by said surface (1A1);

(B) said valve element (1B) has edge portions overhanging opposite sides of said head portion; and

(C) said means (1D) comprises flanges extending downwardly from said key (1C) with portions in contact with the overhanging edges whereby downward movement of said key effects the bowing (ID) of said valve element (1B), and said valve element provides means for returning said key to its original position.

4. A valve according to claim 1 wherein:

(A) said base structure (1A) has a rectangular head portion topped by said surface (1A1);

(B) said valve element (1B) is rectangular with opposite edge portions over-hanging opposite sides of said head portion, and has flexible spring fingers extending upwardly therefrom to support said key (1C) in its position over said valve element; and

(C) said means (1D) comprises abutments depending from said key (1C) in line with the overhanging edges of said valve element (1B).

5. A valve according to claim 1 wherein:

(A) said key (1C) is provided with depending flanges surrounding said top surfaces (1A1) and cooperates with said valve element 1B) to seal the valve against fluid leakage when said valve element is in its bowed shape.

6. A valve according to claim 3 wherein:

(A) said key flanges (3C) surround said head portion (3A) with bottom edge portions turned in under said head portion to lock said key (1C) on said head portion and limit its upward movement (3C) to its original position.

7. A construction according to claim 4 wherein:

(A) said fingers (4B) have less spring force than said valve element (1B) thereby permitting some pretravel of said key (1C) during its depression prior to the bowing of said valve element.

8. A valve construction according to claim 4, wherein:

(A) said valve element (1B) is formed to provide a snap action upon bowing.

9. A fluid flow control valve comprising:

(A) a fluid input channel having an input port;

(B) a fluid outlet port;

(C) a spring leaf valve element positioned over said input port in a manner preventing fluid flow therethrough;

References Cited UNITED STATES PATENTS 2,585,863 2/1952 Smith 25175 X 3,036,592 5/1962 Lips 25175 X 3,224,459 12/1965 Lilly 25175 X M. CARY NELSON, Primaly Examiner.

R. C. MILLER, Assistant Examiner. 

9. A FLUID FLOW CONTROL VALVE COMPRISING: (A) A FLUID INPUT CHANNEL HAVING AN INPUT PORT; (B) A FLUID OUTLET PORT; (C) A SPRING LEAF VALVE ELEMENT POSITIONED OVER SAID INPUT PORT IN A MANNER PREVENTING FLUID FLOW THERETHROUGH; (D) A KEY POSITIONED OVER SAID VALVE FOR RELATIVE MOVEMENT THEREWITH; AND (E) MEANS RESPONSIVE TO MOVEMENT OF SAID KEY IN A DIRECTION TOWARD SAID VALVE TO CAUSE THE VALVE TO ASSUME A SHAPE OVER SAID INPUT PORT OPENING SAID INPUT PORT FOR FLUID FLOW THEREFROM TO THE OUTLET PORT. 